Hi Johannes On Sat, Mar 16, 2019 at 10:56:11AM +0100, Johannes Bauer wrote: > <REDACTED> host > eur.olc.protection.outlook.com[104.47.125.33] said: 550 5.7.1 > Unfortunately, messages from [37.120.172.118] weren't sent. Please contact > your Internet service provider since part of their network is on our block > list (S3150). You can also refer your provider to > http://mail.live.com/mail/troubleshooting.aspx#errors. > [SG2APC01FT051.eop-APC01.prod.protection.outlook.com] (in reply to MAIL > FROM command)
So your _provider_ is on the the MS blacklist. Netcup did not show up on my radar, but I don't know what else. > Here's what I've checked/tried: > * Neither I nor any of my users send spam. The mail volume is VERY low. It is really low, so low that DNSWL did not pick the IP up as recurrent sender or refuse to. > * I use a reputable service provider for my server (i.e., I suspect if > there were other customers in my IP range doing bad things, they'd be > kicked out). Not according to the rejection by MS services. > In my desparation I've even registered to the Google Postmaster thing > and demeaningly "verified" my domain by altering the DNS: > https://postmaster.google.com/ -- all data is entirely empty (even > though there were positively mails blocked since I've registered with them). For the correct domains? I don't see any verification records for spornkuller.de. > > If anyone has any ideas of what could be wrong, I'm absolutely grasping > for straws here. Any help is greatly appreciated. Let's point out the obvious(?): You MTA is known under different names: > johannes-bauer.com mail is handled by 10 johannes-bauer.com. > spornkuller.de mail is handled by 10 spornkuller.de. It does not advertise ESMTP (how the heck did you manage to miss-configure it this much?): | % nc spornkuller.de 25 | 220 Hi there Claim your info at dnswl.org. Regards, Bastian -- The best diplomat I know is a fully activated phaser bank. -- Scotty
